Xing Jiali, Wu Huaxin, Liang Tianyuan, Zhu Shiqing, Ling Qin, Fan Jiyang
Key Laboratory of Quantum Materials and Devices of Ministry of Education, School of Physics, Southeast University, Nanjing 211189, People's Republic of China.
Nanotechnology. 2024 Aug 27;35(46). doi: 10.1088/1361-6528/ad7099.
Copper indium selenide (CISe) is a prototype infrared semiconductor with low toxicity and unique optical characteristics. Its quantum dots (QDs) accommodate ample intrinsic point defects which may actively participate in their rather complex photophysical processes. We synthesize CISe QDs with similar sizes but with distinct highly stoichiometry-deviating atomic ratios. The synthesis condition employing Se-rich precursors yields the Cu-deficient CISe QDs with special photophysical properties. The photoluminescence exhibits monotonic red shift from 680 to 775 nm when the ratio of Cu's proportion to In's decreases. The luminescence is found to stem from the copper vacancy and antisite defects. The CISe QDs exhibit Raman activity at 5.6, 6.9, and 8.7 THz that is separately assigned to Cu-Se and In-Se optical phonon modes and surface mode.
硒化铜铟（CISe）是一种具有低毒性和独特光学特性的典型红外半导体。其量子点（QDs）存在大量本征点缺陷，这些缺陷可能积极参与其相当复杂的光物理过程。我们合成了尺寸相似但原子比具有明显高度偏离化学计量比的CISe量子点。采用富硒前驱体的合成条件产生了具有特殊光物理性质的缺铜CISe量子点。当铜与铟的比例降低时，光致发光呈现出从680纳米到775纳米的单调红移。发现发光源于铜空位和反位缺陷。CISe量子点在5.6、6.9和8.7太赫兹处表现出拉曼活性，分别归因于Cu-Se和In-Se光学声子模式以及表面模式。
